I was a ground dweller when I thru-hiked the AT, but I've done longish hikes (7-15 days) with a set up that could work.
Buy yourself a 3-season phoenix
from Hammockgear.com or a Yeti
from Warbonnet. Great 2/3 length underquilts that are both warm and comfortable.
Then for the footbox, get a Gossamer Gear Nighlight Pad
. I got the 3/4 length (60" long) and trimmed it down to about 48". It goes into the WB sleeve at the feet, and I fold it in half there. But if I need to go to ground, it makes for a tolerable night's rest. I did this last summer when I stayed at a campground on the Benton MacKaye Trail.
It would make for a decent bail option to sleep in a shelter in really bad weather (which is about the only reason I would sleep in a shelter any more). For your feet, just place your empty pack under them.